Document [1] describes a hybrid video encoder which subtracts a prediction from the original signal to generate residual data. These residuals are then transformed block by block, quantized and sent to the receiver. The encoder also comprises a local decoder. The local decoder rescales the quantized transform coefficients and inversely transforms them to generate a representation of the residual data and with it a representation of the original signal. A set of previously decoded pictures stored in the picture buffer is used to generate the prediction signal.
Further prior art video coding systems are described in documents [2]-[6].
The prior art video coding systems include block-based motion estimation for motion compensated prediction at the encoder. This means that motion vectors have to be transmitted as side information. Because inter prediction is one of the major tools to achieve high compression gains, the transmission of motion vectors as side information is a significant task.